Simulation of nonlinear transient elastography: finite element model for the propagation of shear waves in homogeneous soft tissues

International audienceIn this study, visco-hyperelastic Landau's model which is widely used in acoustical physic field is introduced into a finite element formulation. It is designed to model the non-linear behaviour of finite amplitude shear waves in soft solids, typically, in biological tissues. This law is employed in finite element models based on elastography experiments reported in [1], the simulations results show a good agreement with the experimental study : it is observed in both that a plane shear wave generates only odd harmonics and a nonplane wave generates both odd and even harmonics in the spectral domain. In the second part, a parametric study is carried out to analyze the influence of different factors on the generation of odd harmonics of plane wave. A quantitative relation is fitted between the odd harmonic amplitudes and the non-linear elastic parameter of Landau's model, which provides a practical guideline to identify the nonlinearity of homogeneous tissues using elastography experiment